DATA DECODING DEVICE AND ITS METHOD

摘要

PROBLEM TO BE SOLVED: To always set optimum initial weight in soft judgment Viterbi decoding at a floating point and to execute the Viterbi decoding of high error correction ability. SOLUTION: A reception signal l is inputted to a one frame memory 2 and an initial weight operation part 3. The one frame memory 2 delays the reception signal 1 by one frame and inputs it to a floating point ACS processing part 4. The initial weight operation part 3 integrates the amplitude of the reception signal 1 by one frame and inputs it to the floating point ACS processing part 4. The floating point ACS processing part 4 executes an ACS processing with input from the initial weight operation part 3 as initial weight and inputs a path selection result to a trace-back processing part 5. The trace-back processing part 5 reproduces the state transition of an encoder based on input from the floating point ACS processing part 4 and outputs a decoding information system 6.